A new breed of prospectors -- banks, insurers, utility companies -- are receiving billions in subsidies while taxpayer and ratepayers are paying most of the costs. Critics say it's a rip-off.

One of three solar receivers stands 459 feet above the floor of the Mojave… (Mark Boster / Los Angeles…)

Driven by the Obama administration's vision of clean power and energy independence, the rush to build large-scale solar plants across the Southwest has created an investors' dream in the desert.

Taxpayers have poured tens of billions of dollars into solar projects — some of which will have all their construction and development costs financed by the government by the time they start producing power.

The cost for decades to come will also be borne by ratepayers. Confidential agreements between solar developers and utilities lock in power prices two to four times the cost of conventional electricity. The power generated by the mega-plants will be among the most expensive renewable energy in the country.

That high-priced power will compose an increasing share of California's electricity following Gov. Jerry Brown's signing last year of legislation requiring that renewable sources provide 33% of the state's power by 2020.

Stanford University economist Frank Wolak, an expert in the California electricity market, said the state's renewable energy strategy could boost electricity rates 10% to 20%, depending on a number of factors. Potentially, consumers' bills could go up by 50%.

"It is easily in the billions of dollars," he said.

Government and solar officials say the subsidies are no different from long-standing federal support for the oil, gas and nuclear industries. They say generous incentives are necessary to incubate the fledgling renewables industry.

"We are driving clean energy projects that would otherwise not have gotten built at a commercial scale with innovative technology," said Daniel Poneman, deputy secretary of the U.S. Department of Energy.

Energy Department officials say solar energy prices will fall as the industry matures, and the cost of power from future conventional plants will be higher.

Critics, however, say that despite the righteous goal of combating climate change, solar entrepreneurs are getting too much government money.

"What's happening in California is a tragedy, on every front," said Bill Powers, a San Diego-based electrical engineer and power plant consultant to government, nonprofits and developers. "It's a huge waste of money…. I see a lot of this as just an old fashioned rip-off."

The lure of outsized profits has set off a solar frenzy in California, with dozens of projects planned from Barstow to Blythe, from Inyo County's high desert to the Sand Hills in Imperial County.

The spark has been the renewable energy program begun by former President George W. Bush and expanded under President Obama.

The incentives allow solar developers to reap annual returns on their investments of 8% to 12%, as much as tripling their money in a decade. In some cases the returns could go as high as 17%, according to Lee J. Peterson, an Atlanta-based tax attorney at the Reznick Group.

"Banks and Wall Street are trying to outdo one another with green commitments," said Michel Di Capua, a renewable power analyst with Bloomberg New Energy Finance. "It looks good from an environmental perspective. But it is also very profitable."

To make such projects economically attractive for developers, the government created a mix of federal loan guarantees, grants and tax incentives — and threw in the cheap use of millions of acres of public land for power plants.

Taken together, the incentives can provide solar companies with more than half a project's costs in cash, with the remainder covered by the federally guaranteed loans.

The cash grants, approved as part of the 2009 economic stimulus package, provided renewable-energy developers 30% of the cost of a project once it is finished. More than $13 billion has been distributed. The grants are no longer offered. They have been replaced by a tax credit of equal value.

The most complex piece is a tax policy that allowed companies to deduct in one year the entire cost of a project from their taxable income. The program was changed this year, requiring the cost be deducted over five years.

The low-interest, government-guaranteed loans — more than $16 billion for renewable energy projects so far — pay up to 80% of a project's construction costs.

"If this were a modern-day fairy tale — and in many respects it is — solar developers would be saying, 'Mirror, mirror on the ground, look at all the money I found!' " said one county official, who did not want to be identified because of pending negotiations with a solar developer.

One of the biggest solar projects in the world is now rising in the California desert just off Interstate 15 near the Nevada border.